import java.util.ArrayList;
import java.util.List;


public class collecton {
	
		public static void main(String [] args)
		{

		List <String> listOfStrings = new ArrayList <String>();
		String str = "black";
		listOfStrings.add(str);
		listOfStrings.add("white");
		listOfStrings.add(str+str);
		System.out.println(listOfStrings.size());
		System.out.println(listOfStrings.contains("1"));
		System.out.println(listOfStrings.contains("black"));
		System.out.println(listOfStrings.remove("white"));
		System.out.println(listOfStrings.size());
		}
		}

